The monomer 2-acrylamido-2-methylpropane sulfonic acid is known to the art and is commercially available.
A class of monomers characterized as vinyl aminimides are also known to the art. Such aminimide monomers are disclosed, for example, in U.S. Pat. Nos. 3,527,892 and 3,641,145. Reference should also be made to copending application Ser. No. 753,521, filed Dec. 22, 1976 in the names of Avinash C. Mehta, Donald O. Rickter and Lloyd D. Taylor, commonly assigned which discloses monomers of the formula: ##STR1## wherein R is hydrogen or a lower alkyl.
The aminimide group may be represented by the formula: ##STR2##
A novel class of copolymers of 2-acylamido-2-methylpropane sulfonic acid and a vinyl aminimide has now been found.